Electrical and mechanical properties of metallic nanowires: Conductance quantization and localization

Measurements of room-temperature electronic transport in pulled metallic nanowires are presented, demonstrating that the conductance characteristics depend on the length, lateral dimensions, state and degree of disorder, and elongation mechanism of the wire. Conductance during elongation of short wires, l∼50 Å, exhibits periodic quantization steps with characteristic dips, correlating with the order-disorder states of layers of atoms in the wire, predicted via molecular dynamics simulations. The resistance of longer wires, l≳100 Å, exhibits localization characteristics with ln R(l)∼l2. Effects of disorder and variations in wire geometry, exhibited via their influence on the transmittivity of the conductance channels and/or the quantization conditions, are demonstrated.